contraception

Question 1

types of contraceptives

Answer 1

–Injections/implants –Oral contraceptives–Intrauterine device (IUD –hormonal & non-hormonal)–Condoms (male & female)–Diaphragm–Spermicides–Rhythm–Withdrawal–Abstinence–Lactationalamenorrhoea method (LAM)

Question 2

Combined oral contraceptives (COCs)

Answer 2

Oestrogen and progestogen

Question 3

Oestrogens

Answer 3

Natural - estradiol
Synthetic ethinyloestradiol, mestranol
Action
Suppresses FSH
Prevents development of dominant follicle
Stimulates endometrial proliferation
Potentiates the action of the progestogen

Question 4

Oestrogens side effects

Answer 4

Side effects–Nausea, vomiting, breakthrough bleeding
Breast tenderness
Fluid retention
Change in libido
Chloasma
Metabolic effects
↑HDL, ↓LDL, ↑triglycerides
↑coagulation factors
↓bone resorption

Question 5

Progestogen MOA

Answer 5

Suppresses LH surge (blocks ovulation)
Suppresses endometrial proliferation
Thickens cervical mucus (impermeable)
Produces secretory endometrium (prevents cancer of the endometrium)

Question 6

Progestogen side effects

Answer 6

Side effects
Menstrual irregularity
Nausea
Bloating, weight gain
Breast tenderness
Acne
Change in libido
Mood changes
Metabolic effects (?)–↓HDL, ↑LDL

Question 7

COCs

Answer 7

Most common form of oral contraception

Combined effect of oestrogen and progestogen
Inhibit ovulation
Endometrium does not develop normally and the absence of a corpus luteum prevents the preparation of an endometrium suitable for implantation
So even if ovulation occurs implantation is unlikely

Question 8

Absolute contraindications for COCs

Answer 8

Less 6 weeks postpartum
Smoker over the age of 35 (>15 cigarettes per day)
Hypertension (systolic > 160mmHg or diastolic > 100mmHg)
Current or past history of venous thromboembolism (VTE)
Ischemic heart disease
History of cerebrovascular accident
Complicated valvular heart disease (pulmonary hypertension, atrial fibrillation, history of subacute bacterial endocarditis)\
Migraine headache with focal neurological symptoms
Breast cancer (current)•Diabetes with retinopathy/nephropathy/neuropathy
Severe cirrhosis
Liver tumour (adenoma or hepatoma)

Question 9

Risks with COCs (adverse effects)

Answer 9

Breakthrough bleeding (usually transient)
Nausea
Breast enlargement & tenderness
Headache
Fluid retention
Chloasma

Question 10

When should COCs be used?

Answer 10

Ovarian and endometrial cancers
Ovarian cysts
Pelvic inflammatory disease

Benefits outweigh risks
Relief of menstruation related problems

Question 11

Drug interactions with oestrogen

Answer 11

Hepatic enzyme(CYP3A4) inducers e.g. rifampicin,
phenytoin,
carbamazepine–Require high dose COC
Other
Orlistat,
St John’s
Wort

Question 12

Vaginal ring

Answer 12

Over the course of 3 weeks, ring releases a continuous low dose of oestrogen and progestogen

Question 13

Progestogen-only pills

Levonorgestrel, norethisterone

Answer 13

Thickens cervical mucus, making it more difficult for sperm to penetrate and reach the ovum
Makes the endometrium unsuitable for implantation

Indications–Women who are unable to take oestrogens 
Breast feeding (do not dry up breast milk whereas oestrogens do)

Question 14

Adverse effects of progestogen-only pills

Answer 14

Menstrual irregularities e.g. changes in cycle length, spotting, total amenorrhoea
Depression
Weight gain

Question 15

Oral emergency contraception

Answer 15

Success rate increases if taken as soon as possible after unprotected sex

Question 16

Copper IUDs

Answer 16

Copper wire is wound around the stem of the T-shaped IUD
Copper ions leach into uterine fluids and cervical mucous toxic to sperm
Even if sperm fertilises egg - inflammatory reaction within endometrium prevents implantation